A man was critically injured and another person was taken to hospital as emergency crews responded to a series of explosions and fire at a hazardous waste facility in St. Catharines, Ont., on Thursday.
The explosions triggered the evacuation of nearby homes for most of the day as crews worked to put out the large blaze.
Police said emergency crews were called to the Ssonix Products facility at 20 Keefer Rd. just after 6:30 a.m. ET. The company's website said its line of business includes producing gasoline, kerosene, distillate fuel oils, residual fuel oils and lubricants.
Crews found a fire that had spread to a neighbouring industrial building as well.
Karen Lutz-Graul, deputy chief of operations with Niagara Emergency Medical Services, told CBC Hamilton that one person with life-threatening injuries was transported to hospital.
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A second person "with a serious complaint" was also taken to hospital, Lutz-Graul said. That individual did not suffer a physical injury.
'Black plume' of smoke
St. Catharines fire department Chief Dave Upper said the injured man was working at the hazardous waste facility and the only person there at the time of the explosion.
"We know the patient is conscious but has received significant burns," Upper said. "We're still working defensively on the fire."
Upper said the injured man was initially taken to a local hospital, but has since been transferred to the burn unit at Sunnybrook Health Sciences Centre in Toronto.
A neighbourhood north of the facility was evacuated due to a "black plume" of smoke blowing toward the area, Upper said, with residents sent to a community aquatics centre.
Shortly after the explosion, police tweeted: "Officers [are] evacuating nearby homes and businesses."
They said residents should "stay indoors, out of the smoke."
Around 5 p.m., Upper said while fire crews remained on scene, the fire was "now under control" and they were putting out "hot spots."
The Ministry of the Environment concluded the air quality was "clean and safe" for workers and residents, Upper said, announcing the city was allowing residents to return home.
The access roads into the neighbourhood have reopened, he added, though Keefer Road remained closed.
Fire crews heard multiple explosions
Early Thursday morning, fire crews heard multiple explosions at the facility for about 45 minutes after they arrived, Upper said earlier in the day. The owner of the facility was on the scene and had told fire crews about various chemicals that were in the building, he said.
"We are concerned that there are some cleaning agents in the one bay and we're trying to determine the level of the fire, how far it's extended and our exposure to that area," he said.
Crews were also trying to ensure run-off water from their efforts didn't collect in nearby Lake Ontario, Upper said, and a hazardous materials company has brought in marine-containment booms.
"We're working to stem the water from flowing into the lake, and then whatever's into the lake right now we're trying to capture."
Utter said about 50 residents had been housed at the St. Catharines Kiwanis Aquatic Centre before determining the neighbourhood was safe.
One evacuee, Bruno Caciagli, told CBC News on Thursday afternoon, before people were allowed to return home, that he was preparing his breakfast when the explosion occurred.
"The house shook as if we're in the middle of an earthquake," Caciagli.
He said he heard "a second explosion, not as loud as the first, and it did not shake the house like the first one. And then one minute after that, another explosion ... the sky turned absolutely red. It was like watching the sun coming up on a clear day."
Another resident, Carol Green, said her husband was walking their dogs when they "heard a loud bang followed by a huge orange glow in the sky."
Green said this was "followed by more explosions."
"I was at home," she said, about four kilometres away from the explosion. "[And] the whole house shook."
Residents were told to shelter in place
St. Catharines Fire Services said earlier in the day that people living in the area outside of the Blossom, Parkside or Moes subdivision should shelter in place.
"Close your windows and doors and turn off your furnace to avoid letting air get in," a tweet from the service read, before the city said the air quality had determined to be safe.
Additionally, St. Catharines Fire Services said the Ministry of Environment, Office of the Fire Marshal, Technical Standards and Safety Authority, and a hazmat remediation team had all been contacted and would be attending the fire.
Gary Wheeler, spokesperson for the Ontario Ministry of the Environment, Conservation and Parks, said that prior to the fire, Ssonix did not have any ongoing environmental compliance issues.
Wheeler said ministry staff will continue to ensure the fire-douse water is managed properly, and the property owner was taking steps to ensure any impact to the environment is remediated.
"We are monitoring air quality in the area to support emergency services for the duration of the emergency, and we will ensure that the appropriate assessment of impacts to soil, groundwater and surface water is undertaken, and any necessary cleanup is completed." Wheeler said.